1. Field of Invention
An overhead lift apparatus defines a frame having tracked lateral clamp arms defining three rotatable and spreadable wheels on opposing ends of the frame activated by a hydraulic spreading and retracting means, the lateral clamp arms clamp onto an inner surface of an upper portion of a welded ring lifting the ring for transfer from one location to another without deformation of the ring, including additional outriggers with additional wheels to expand the diameter size for larger rings, and larger cylindrical vessels.
2. Description of Prior Art
A preliminary review of prior art patents was conducted by the applicant which reveal prior art patents in a similar field or having similar use. However, the prior art inventions do not disclose the same or similar elements as the present ring clamp device, nor do they present the material components in a manner contemplated or anticipated in the prior art.
There were two types of devices that were functionally suited for the lifting or movement of a cylindrical object, primarily coils of materials. These devices included clamping mechanisms that either engage a coil or cylinder from one side or engage a coil from opposite ends, the coil being handled by the device not being the type that experiences any significant deformity when lifted or where deformation does not cause any significant concern.
The type of clamps which engage a coil or roll from both sides are incorporated within or defined by U.S. Pat. No. 6,558,108 to Van Oord, which includes a lifting mechanism for large roll on a horizontal axis, U.S. Pat. No. 6,325,434 to Takao, which is a scissor clamp for lifting a cylindrical object, U.S. Pat. No. 5,205,599 to Wassmer, defining a non-deforming margin roller lift, U.S. Pat. No. 4,709,953 to Sirota, which discloses an over lift mechanism for a spooled material, U.S. Pat. No. 4,641,876 to Kiser, which is identical to Wassmer, U.S. Pat. No. 4,368,913 to Brockman, and U.S. Pat. No. 1,969,873 to Bradford. In U.S. Pat. No. 3,655,232 to Martelee, a clamp device is disclosed with outer arms being expanded and contracted along a guided track in a central frame using a hydraulic piston to expand and contract the distance between the outer arms, the arms guided on a horizontal plane within the tracks of the frame.
Single arm lifts are disclosed in U.S. Pat. Nos. 597,438 to Schilling, which appears to be a balanced C-shaped object that grabs an inner diameter of a pipe, but does not express any concern over deformity of the object, and U.S. Pat. No. 3,999,665 to Rogers, which discloses a single transfer bar which carries a coiled material. Other patents disclose lift devices that engage some or all of an inner diameter of a cylindrical object, including U.S. Pat. No. 4,358,143 to Cullen, and U.S. Pat. No. 5,895,198 to Lofstrom, with Lofstrom expressing some concern over maintaining the curvature of a cylindrical or partially cylindrical object during lift and carry.